Calculated initial vacancy ratios (<em>I</em><sub>L</sub> = <em>I</em>_{{
m KL}^{1}}:<em>I</em>_{{
m KL}^{0}}), extrapolated x-ray intensity relative to the main line (<em>R</em><sub>L</sub> = <em>X</em>_{{
m KL}^{1}}:<em>X</em>_{{
m KL}^{0}}) and to the total intensity (<em>R</em><sub>T</sub> = <em>X</em>_{{
m KL}^{1}}:<em>X</em>_{{
m KL}^{0}+{
m KL}^{1}}), average differences in <em>X</em>_{{
m KL}^{1}} intensity between oxides and pure elements extracted from the literature (ΔR<sub>L</sub>), and the product effect on the total x-ray yield
C M Heirwegh
I Pradler
J L Campbell
10.6084/m9.figshare.1012792.v1
https://iop.figshare.com/articles/dataset/_Calculated_initial_vacancy_ratios_em_I_em_sub_L_sub_em_I_em_span_xmlns_xlink_http_www_w3_org_1999_x/1012792
<p><b>Table 1.</b> Calculated initial vacancy ratios (<em>I</em><sub>L</sub> = <em>I</em>_{{\rm KL}^{1}}:<em>I</em>_{{\rm KL}^{0}}), extrapolated x-ray intensity relative to the main line (<em>R</em><sub>L</sub> = <em>X</em>_{{\rm KL}^{1}}:<em>X</em>_{{\rm KL}^{0}}) and to the total intensity (<em>R</em><sub>T</sub> = <em>X</em>_{{\rm KL}^{1}}:<em>X</em>_{{\rm KL}^{0}+{\rm KL}^{1}}), average differences in <em>X</em>_{{\rm KL}^{1}} intensity between oxides and pure elements extracted from the literature (ΔR<sub>L</sub>), and the product effect on the total x-ray yield. Absolute uncertainties are listed in parentheses.</p> <p><strong>Abstract</strong></p> <p>Proton-induced x-ray emission (PIXE) was used to assess the accuracy of the National Institute of Standards and Technology XCOM and FFAST photo-ionization cross-section databases in the low energy region (1–2 keV) for light elements. Characteristic x-ray yields generated in thick samples of Mg, Al and Si in elemental and oxide form, were compared to fundamental parameters computations of the expected x-ray yields; the database for this computation included XCOM attenuation coefficients. The resultant PIXE instrumental efficiency constant was found to differ by 4–6% between each element and its oxide. This discrepancy was traced to use of the XCOM Hartree–Slater photo-electric cross-sections. Substitution of the FFAST Hartree–Slater cross-sections reduced the effect. This suggests that for 1–2 keV x-rays in light element absorbers, the FFAST predictions of the photo-electric cross-sections are more accurate than the XCOM values.</p>
2013-09-06 00:00:00
product effect
oxide form
vacancy ratios
light element absorbers
National Institute
Technology XCOM
kl
FFAST predictions
pixe
Absolute uncertainties
XCOM attenuation coefficients
XCOM values
intensity
light elements
rl
parameters computations
rt
il
Atomic Physics
Molecular Physics